Well, in the picture I saw some flaws. This old man is a technological expert, as well as suffers from age. Thus, no holograms "far away" to show the hour...

I see it more like first an hologram of quite enlarged numbers flat on top of his wrist (to cope with his aged sight).

Then he would press some surface area in the watch wand and the numbers would "rise" and convert to the size of an Ipad screen (or a little larger), as in fact this is really a wrist-pad, and he would twist it so that the people can see it (like he would do when showing a presentation), while a nice voice tells the "audience" the hour.

I will see if I can have some 3D design, but it should be something minimalist in design, like current phones and the like...

You're jumping into a crowded pool. See http://blogof.francescomugnai.com/2013/07/20-of-the-coolest-steampunk-watches-ive-ever-seen/ for only one example.

May I suggest the time-honored hacker practice of case-modding? The reason I suggest it is that whatever the end result is, it should be a working watch, that can be used to tell time. This will mean starting with a working watch (preferably with a traditional geared mechanism), and customizing to get a steampunk appearance.

Do feel free to photoshop in the appropriate 3D holograms coming from an appropriate display attachment

(Of course, you could try designing the mechanism and making that on a 3D printer, but I'd call that an exercise in frustration.)

After all, what good engineer would submit a non-working prototype? Just say the holographic projector wasn't quite ready by contest time, but will be in the next hardware revision. :-)

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